Study finds highly sensitive people's brains work differently

The colored areas in this fMRI composite show the areas of the brain that experience greater activity in highly sensitive people than in people with low sensitivity.

Photo:Stony Brook University

A recently published study by Stony Brook University psychologists has revealed there are underlying neurological processes behind highly sensitive people's reactions to emotional images.

Published in the journal “Brain and Behavior,” the study by married research professors Arthur and Elaine Aron shows sensitive people — who have a heightened awareness of their surroundings and of details oft overlooked by the majority of the population — experience more activity in certain parts of the brain when they're exposed to pictures of emotional individuals than the average observer.

It is the first neuroimaging study to provide a glimpse inside the minds of "HSPs" in an attempt to gauge how their brains responded to other people's emotions.

The 20 percent of people who fall into the official medical classification of highly sensitive had frequently reported that they had an especially strong empathetic response to emotional cues from others, but the claim had never been examined directly, Arthur Aron said in an interview with FiOS1 News. "We wanted to test this in a rigorous way," he said.

In American culture, hypersensitivity — which often results in shyness and hesitancy — is generally thought of as a character flaw, the scientist said. But over the decades, researchers have come to view it as less of a personal failing than the result of neurological activity.

"What is going on, and these data support it further, is that [highly sensitive people] process information more thoroughly," the research professor said.

Scientists have found that HSPs are individuals whose brain function makes them more conscious of their settings, meaning they are more strongly affected by loud noises, more apt to notice scents, and they pick up on subtleties that others overlook, Arthur Aron said. Often, the subjects have a strong appreciation for the fine details of art and music, he added.

Such personalities can be a double-edged sword, he said. Hyper-sensitive wild animals can be more apt than the rest of the pack to spot predators, but their tendency to hang back and use caution can sometimes mean they will lose out when competing for food, Aron said.

Neurologists had never conducted an in-depth study of how highly sensitive people respond to others' emotions, until now. Two-and-a-half years ago, the Arons, and lead researcher Bianca Acevedo of the University of California, Santa Barbara, decided to conduct such a probe while performing another unrelated study on newlyweds in California. Both of the reviews were funded by the National Science Foundation.

The researchers used functional magnetic resonance imaging (fMRI) to scan the brains of 18 subjects, some of whom had been classified — based on their answers to a questionnaire — as highly sensitive. The fMRI scans were performed while the subjects looked at photos of smiling and sad faces, and found that the areas of the brain involved with awareness and empathetic feelings in the HSPs had much greater blood flow than was seen in people with low sensitivity.

“This is physical evidence within the brain that highly sensitive individuals respond especially strongly to social situations that trigger emotions,” the Arthur Aron said in a statement on the findings.

The researchers were surprised to find that their subjects showed greater neurological activation when viewing positive emotions rather than negative ones. "We didn't expect that. We thought it would be more even," Aron told FiOS1 News Wednesday.

That was good news for people whose condition previous research had cast as largely problematic, because it could exacerbate the fear and stress brought on by a tense situation, he said.

The team's work added to a body of research that has helped highly sensitive people to better understand and accept their behavior.

Traditionally hypersensitivity "is looked down upon, particularly in men, and people think, 'What is wrong with me?' But it is a natural, normal trait, with advantages and disadvantages," he said.

The Arons are also starting to research the effects of psychiatric medications on HSPs, since such patients, if they suffer from a clinical condition, might require a different course of treatment than other people would.